The invention relates to an installation for extinguishing fire, the installation comprising a number of spray heads, a pipe system for leading extinguishing medium to the spray heads, the spray heads comprising a holder body having an inlet for incoming extinguishing medium and at least one nozzle. The installation can be used both in open and closed spaces.
The invention relates further to a combination of a means of transportation and an installation for extinguishing fire. The expression means of transportation refers here to all kinds of vehicles, such as trains, lorries, ships as well as semitrailers, such as railway wagons (especially open ones) and trailers (especially open ones) for these vehicles.
The invention relates also to a combination of a tunnel and an installation for extinguishing fire.
The invention relates further to a spray head comprising a holder body, an inlet for incoming extinguishing medium and at least one nozzle.
One of the greatest problems with fire fighting installations is to make the fire detection synchronized with the actual fire extinction in such a way that the fire extinction occurs as fast as possible at the site of the fire.
An installation for extinguishing fire is known from WO 93/10860. This installation comprises a number of spray heads arranged in groups in such a way that each group comprises a number of spray heads. A spray head of each particular group comprises a heat-activated release means. When this melts or explodes on account of heat, the installation is arranged to deliver extinguishing medium to the other spray heads of the group. The other groups do not release. In order to make a further group release, the release means of this further group has to explode or melt. This known construction enables spraying extinguishing medium to a limited area in the vicinity of the fire without extinguishing medium being sprayed in areas with no fire, and in this manner, it is possible to manage with a relatively small amount of extinguishing medium.
This known installation normally functions well. However, there are environments where an installation of this kind does not function satisfactorily or cannot function at all. In this connection, reference is made e.g. to environments where the spray heads are exposed to dirt, deposits and impurities of different kinds leading to the fact that the components of the spray heads, such as nozzles and heat-activated means, cannot function (the nozzles are blocked; the heat-activated release means do not function satisfactorily, because they respond poorly to the heat from fire, since they are very dirty). An example of such an environment is e.g. an open railway wagon. Open railway wagons are used for transporting vehicles and other equipment and goods that can be inflammable and thus constitute a fire risk. If a conventional fire fighting installation were installed in an open railway wagon, it would become too dirty to function in a relatively short time. Even in covered railway wagons (and trailers), such goods can be transported which very quickly make the railway wagon (trailer) dirty, and therefore, the present invention can also be applied to covered railway wagons (and trailers). Other examples of such environments are painter's shops and steel works.
In certain environments, e.g. railway wagons, tunnels, car decks, high storage, where the fire may develop fast, it is desirable to control the fire in such a way that not too big an area is covered by releasing sprinklers. To divide the installation into sections, as shown in WO 93/10860, is not a sufficient solution for providing effective fire extinction, because in such environments, sprinklers release also in irrelevant sections (sections with no fire). A fire fighting installation with a known structure and mounted in a means of transportation, such as an open railway wagon, would thus in any case function unreliably for that reason alone that, because of wind conditions, hot gases generated at fire flow fast to such areas where there is no fire at all, the consequence being that extinguishing medium is delivered to a wrong area, i.e. an area with no seat of fire. This leads to a loss of extinguishing medium and constitutes an essential drawback in an application to a means of transportation, because vehicles have a limited capacity of transporting extinguishing medium, in practice. Further, delivering extinguishing medium to a "wrong" area may result in material damages. A typical example is constituted by a train driving at a speed of 140 km/h when a fire breaks out. The heat from the fire spreads and the ampoules of the sprinklers explode at a place far from the actual fire, which leads to that extinguishing medium, such as water, is sprayed to a wrong place. In tunnels and garages, hot exhaust gases from lorries can be directed straight up towards sprinklers, which also results in that sprinklers release without a fire or even without a risk of fire.
On the basis of this, these difficult environments in many cases lack fire fighting installations, in spite of that a functioning fire fighting installation would be of great use.
Mechanical loads can also make a fire fighting installation function unnecessarily (especially in case of a breakage of the release means of the installation). Such mechanical loads may arise at impacts by trucks, lorries, etc.
There are also fire fighting systems in which the pipes leading to the sprinklers initially contain no water, which depends on the risk of freezing or on weight problems. It takes a certain time (typically 60 s) to fill the pipes and a fire broken out quickly may release too many sprinklers before the water reaches the sprinklers. Examples of environments where the fire may develop quickly are ships transporting vehicles: a fire on a ship deck may spread quickly.
In certain environments, there is a risk that the fire starts explosively. In such an environment, it is probable that all ampoules of a fire fighting installation release by the pressure of the explosion, which makes it impossible for the installation to function effectively to fight the fire. Examples of the last-mentioned environments are transformers, paint cabinets and paint stores.